The invention relates to a method and apparatus for flowing a treating liquid into contact with substantially all of the fluid and equipment in or around a selected bottom portion of a well. More particularly, the invention relates to using a combination of a specified well completion apparatus and treating liquid injecting procedure to effect a dispersion of the treating liquid within a selected portion of the well.
Well treating liquids are well known. Such fluids include scale inhibitors, comprising liquids which are commonly squeezed into the production interval of a well and subsequently allowed to precipitate or be absorbed on the rocks so that they are gradually returned to the wellbore by fluids being produced. Scale inhibitors are described in U.S. Pat. Nos. such as 3,943,059; 3,704,750; 3,661,785; 3,633,672; 3,483,925 and 3,467,192. Other treating liquids comprise hydrate inhibitors such as those described in U.S. Pat. Nos. such as 3,676,981 and 4,235,289. Reservoir acidizing fluids are or form treating liquids which are injected into a reservoir interval to dissolve solids from pore spaces in and around the borehole. Hydrocarbon fluids such as solvents or oil-emulsifying surfactant systems, for removing organic solids from fluid passageways in and around the borehole, comprise another type of well treating liquids, etc.
However, as discussed in U.S. Pat. No. 4,399,868 by E. A. Richardson and W. B. Fair, Jr., where a well contains in a relatively dense brine, it is often difficult to cause a relatively light liquid such as an organic solvent to contact perforations or other passageways below the top of a column of the brine. U.S. Pat. No. 4,399,868 describes a process for injecting a nitrogen gas-generating aqueous liquid solution (optionally accompanied by an organic solvent) to sink below the brine and generate heat and gas to disperse hot liquid into contact with the materials near the bottom portion of the reservoir interval.